Volcano eruptions are both complex and exciting as they display a variety of eruption style depending on the form and the shape related to each type of volcano. Each characteristic has its own effect on the environment. Also, the volcanic activity level is determined by the volcano eruptions.

Saturday, March 10, 2007

Indonesia tries to put an end to mud volcano eruption

For nine months, a gaping hole in the ground has spit out a biblical torrent of hot, black mud, swallowing thousands of homes outside Indonesia's second-largest city and attracting amazed geologists from around the world. Most say the flow is unstoppable, but Indonesian experts refuse to listen, and they have recently begun carrying out a scheme straight from a Hollywood movie: dropping nearly 1,500 concrete balls into the mouth of the mud volcano.Indonesian workers drop some of the 150-pound concrete balls into the mud volcano on Thursday. The unusual plan will cost $130 million, officials say. 'We know lots of people think this is a crazy idea. But we think it will work,' says professor Satria Bijaksana, one of three geologists leading the effort. The mud flow has covered thousands of homes. "We know lots of people think this is a crazy idea," said professor Satria Bijaksana, one of three geologists behind the $130 million plan aimed at reducing the spew by as much as 70 percent. "But we think it will work."

Mud volcanos are fairly common along volatile tectonic belts.

But the eruption just outside the city of Surabaya is exceptional because of the sheer volume of mud that has been surging from the hole — enough to fill 50 Olympic-sized swimming pools each day. Twelve villages and 20 factories have been swallowed, with mud-caked roofs and the tops of lamp posts as the only reminders of what once was there.

Some scientists suggest the rupture was triggered by improper drilling at a nearby natural gas site. Other research points to a major earthquake two days before the mud first appeared in a rice field in May 2006.

Engineers are using a pulley system to hoist beachball-sized concrete spheres over the crater and drop them from a height of about two stories. The balls, each weighing about 150 pounds, are chained together in clusters of four. So far, nearly 150 have been tossed into the abyss, too few to have an impact.

Critics say almost everything depends on the shape of the volcano's gullet, believed by the ball-dropping team to resemble a champagne glass, although recent sonar readings indicate it might be larger than that. "The hope is that the balls will fit snugly at the bottom, but it is unlikely to be that simple," said Richard Davies, a geologist at Britain's Durham University who has studied the mud volcano.

Another concern is that if the hole is blocked, pressure will build up behind the balls and trigger eruptions elsewhere. "It's like putting your thumb at the end of a hose pipe — a fairly rotten hose which could spring a leak anywhere along its length," Davies said.

But with scientists predicting the mud could flow for decades or even centuries, those who have been made homeless say it's worth a shot.

The displaced residents are living in a former market near the site.

"They can't just give up, they have to fight this mud," said Subagio, 49, a father of four who, like many Indonesians, uses only one name. "We have no home, no job, nothing. And who knows how long we will be able to stay here?"